VCSEL based optical links in burst mode

Abstract

Devices and methods are provided to reduce the wake-up time of a Vertical Cavity Surface Emitting Laser (VCSEL) used in a data communication link. For example, in one aspect, a method for optical communications includes, in an optical communication device including a light-emitting device, applying a bias current to the light-emitting device and transmitting a pulse to the light-emitting device before transmitting a preamble signal or data signal to the light-emitting device, wherein the pulse has a voltage greater than a highest voltage of the preamble signal or data signal.

What is claimed is: 
     
       1. A method for optical communications, comprising:
 in an optical communication device comprising a light-emitting device, applying a bias current to the light-emitting device; and 
 transmitting a pulse to the light-emitting device before transmitting a preamble signal or data signal to the light-emitting device, wherein the pulse has a voltage equal to or greater than a highest voltage of the preamble signal or data signal; 
 wherein the bias current in the optical communication device in which the pulse is transmitted is reduced during periods of no data to save power, compared to a bias current that is applied in an optical communication device in which the pulse is not transmitted. 
 
     
     
       2. The method of  claim 1 , wherein the light-emitting device is a semiconductor laser. 
     
     
       3. The method of  claim 2 , wherein the semiconductor laser is a Vertical Cavity Surface Emitting Laser. 
     
     
       4. The method of  claim 1 , wherein the bias current is generated by a bias current source and the pulse is generated by the bias current source. 
     
     
       5. The method of  claim 1 , wherein the bias current is generated by a bias current source and the pulse is generated by circuitry other than the bias current source. 
     
     
       6. The method of  claim 1 , wherein the pulse is generated by a voltage multiplier circuit. 
     
     
       7. An optical communication device, comprising:
 a light-emitting device; 
 a bias current source adapted to apply a bias current to the light-emitting device; and 
 a pulse generator adapted to generate and transmit a pulse to the light-emitting device before a preamble signal or data signal is transmitted to the light-emitting device, wherein the pulse has a voltage equal to or greater than a highest voltage of the preamble signal or data signal; 
 wherein the bias current in the optical communication device in which the pulse is transmitted is reduced during periods of no data to save power, compared to a bias current that is applied in an optical communication device in which the pulse is not transmitted. 
 
     
     
       8. The method of  claim 7 , wherein the light-emitting device is a semiconductor laser. 
     
     
       9. The device of  claim 8 , wherein the semiconductor laser is a Vertical Cavity Surface Emitting Laser. 
     
     
       10. The device of  claim 7 , wherein the bias current is generated by a bias current source and the pulse is generated by the bias current source. 
     
     
       11. The device of  claim 7  wherein the bias current is generated by a bias current source and the pulse is generated by circuitry other than the bias current source. 
     
     
       12. The device of  claim 7 , wherein the pulse is generated by a voltage multiplier circuit. 
     
     
       13. A computer program product for performing optical communication, the computer program product comprising a non-transitory computer readable storage medium having program instructions embodied therewith, the program instructions executable by a computer, to cause the computer to perform a method comprising:
 in an optical communication device comprising a light-emitting device and a bias circuit, applying a bias current to the light-emitting device; and 
 transmitting a pulse to the light-emitting device before transmitting a preamble signal or data signal to the light-emitting device, wherein the pulse has a voltage equal to or greater than a highest voltage of the preamble signal or data signal; 
 wherein the bias current in the optical communication device in which the pulse is transmitted is reduced during periods of no data to save power, compared to a bias current that is applied in an optical communication device in which the pulse is not transmitted. 
 
     
     
       14. The computer program product of  claim 13 , wherein the light-emitting device is a semiconductor laser. 
     
     
       15. The computer program product of  claim 14 , wherein the semiconductor laser is a Vertical Cavity Surface Emitting Laser.